Here is the professional, SEO-optimized English product description for your Infinix Hot 30i (BL-49NX) replacement battery:

Infinix Hot 30i Replacement Battery (BL-49NX) – 100% Premium Quality

Is your Infinix Hot 30i dropping power too quickly, heating up during use, or failing to survive a full day of scrolling and streaming? Bring back its factory-fresh endurance with our premium-grade BL-49NX replacement battery. Specifically manufactured to meet strict performance standards, this high-capacity battery provides the steady and efficient power supply your phone needs to keep up with your daily apps, calls, and entertainment just like day one.

Key Features:

• Flawless Physical Fit: Tailored precisely for the Infinix Hot 30i (Battery Model: BL-49NX / Model: X669, X669C, X669D), ensuring an exact structural match and secure connector alignment with your phone's internal layout.

• True 5000mAh Power Capacity: Packs a full standard 5000mAh capacity to completely restore your device's long screen-on time and reliable daily backup performance.

• Smart IC Circuit Protection: Equipped with an integrated intelligent microchip that actively protects your smartphone from over-charging, over-discharging, unexpected overheating, and short-circuits.

• High-Density Lithium Polymer Cells: Built using advanced Lithium-ion polymer technology for stable voltage output, entirely eliminating sudden percentage jumps or unexpected power cuts.